condition mean min max ZT0-3 3.9464024999999996 3.467005 4.4258 ZT4-7 8.257745 8.257745 8.257745 ZT8-11 8.19659 8.19659 8.19659 ZT12-15 0 0 0 ZT16-19 8.693965 8.693965 8.693965 ZT20-23 7.61828 7.61828 7.61828